The present invention relates to media systems, more particularly, but not exclusively to a personal media playing system.
Hi-Fi systems adequately reproduce audible frequencies. However, the large variety of personal media playing systems that is available to today's media consumer does not.
Among widely used personal media playing systems are MP3 players, portable DVD players, as well as smart cellular telephones (such as Apple™ iPhone or Samsung™ Galaxy S) that can store and reproduce recorded music or movies.
Current personal media playing systems provide stereo sound to users via conventional earphones and/or small speakers.
In personal systems, the low frequency (bass) components of music is often lost. Although such earphones and small speakers adequately provide vocal and melody (mid frequencies), they do not adequately reproduce lower frequencies which are not picked up by the ear-drum, but rather through the body vibrating, particularly the thorax and diaphragm. Bass signals are highly attenuated and infrasound is not transmitted at all. Consequently, earphones and portable speakers do not provide a satisfactory sensory experience that is analogous to that experienced in a night club, or theater during a live performance by a big orchestra or a rock band.
Conventional bass speakers, commonly known as sub woofers, are large and bulky. Personal music systems, whether small speakers on MP3s and smart-phones, or earphones and earplugs do not provide the bass experience.
In a disco or concert hall, much of the bass is felt through the body rather than through the ears, with some of the signal being transmitted via the floor to the feet.
Sub-sonic vibrations (infrasound), if felt, may provide a spooky sensation. However, such frequencies require very big speakers to reproduce.
There have been various attempts to overcome this problem and to provide an illusion of bass by attaching vibrating devices to the shoes or body of the ‘listener’. Such vibrating devices vibrate with the beat of a musical composition, and, when combined with the aural-reception of higher frequencies via earphones or small speakers, provide an enhanced sensation when compared to that of earphones and small speakers without the added sensation from such vibrating devices.
U.S. Pat. No. 6,982,696 to Shahoian describes a moving magnet actuator for providing haptic feedback. The system described has a static solenoid with a W-shaped core about which magnets oscillate. To allow high amplitude of vibration, this arrangement requires high power consumption. The W-shaped core permits a linear relation between magnetic force and displacement, but does not have a smooth attack or recession. The bar magnets have also been found to have a high gradient of magnetic field which also creates preferred harmonics and prevents smooth response at different and changing frequencies. The actuator thus does not provide good sound reproduction, and has poor fidelity.
PCT Application No: PCT/IB2011/053233 filed on Jul. 20, 2011 describes a vibrating transducer that may be fastened to the body or clothing and which enhances the sensation to wearers who additionally receive higher frequencies through earphones. PCT Application No: PCT/IB2011/053765 filed Aug. 28, 2011 describes a wearable transmission device. The base vibrating devices described in these earlier attempts to overcome the inherent limitations of personal music systems are able to follow the beat of some music, and also to differentiate between a range of frequencies and the subject thus has a music experience with the low vibrations sensed through the body. It will be appreciated that the higher the fidelity of the electrical to mechanical signal conversion, the better the sound reproduction.